1. Field of the Invention
The present invention relates to heat dissipating structures, and more particularly, to a heat dissipating structure for use with an electronic equipment casing.
2. Description of the Prior Art
A variety of electronic equipment nowadays, host computers in particular, are internally installed with various peripherals capable of high-speed computation, such as CPU, interface cards, high-capacity memory units (hard disk drives), DVD, CD/DVD-R/RW drives, power supplies, etc. Inside an airtight casing of a host computer, peripherals and electronic components in operation generate heat of different temperatures. The CPU performs computation at high speed and thereby is the largest heat-generating component inside the host computer. A problem that calls for immediate solution involves efficient elimination of heat generated from within a host computer, an operating CPU especially. Manufacturers usually install additional heat-dissipating devices in the host computers or electronic apparatus/equipment such that the heat-dissipating devices reduce ambient temperature or temperature of components inside the host computers or electronic apparatus/equipment.
Referring to FIG. 1, which is a perspective view of the prior art, a computer casing 1 taught by the prior art is installed with a motherboard 2 therein. The computer casing 1 has a rear side formed with a venting hole 11. The motherboard 2 is installed with a heat-generating source 21 thereon. The heat-generating source 21 is installed with a cooling fan 22 thereon. The cooling fan 22 in operation moves an air stream to cool down the heat-generating source 21 and dissipate heat therefrom. After having been moved by the cooling fan 22 to cool down the heat-generating source 21, the air stream lingers in the vicinity of the heat-generating source 21 and stays so far from the venting hole 11 that it is necessary to additionally install a ventilation fan 13 at the venting hole 11 so as to vent heat out of the computer casing 1.
According to the prior art, not only is heat generated by peripherals and electronic components installed in a host computer confined to the casing of the host computer, but a plurality of heat sources present inside the casing of the host computer generate heat concurrently, and thus heat is accumulated inside the casing in the same way as the mechanism for greenhouse effect. Hence, it is necessary to additionally install a ventilation fan to facilitate convection between air streams otherwise shut inside the casing and air streams outside the casing. However, the extra ventilation fan always consumes extra power otherwise available to the computer, and thus voltage of the internal power supply system of the computer is rendered unstable. Accordingly, the prior art has the following drawbacks:    1. inefficient heat dissipation,    2. power-consuming, and    3. inefficient convection between air streams inside a casing and air streams outside the casing.